UV Experiment - Blocking UV Rays

UV Experiment – Blocking UV Rays

See how old prescription bottles have the power to block UV rays.

Don’t throw away your old prescription bottles. Solar science educator, Jim Stryder, shares a unique method of demonstrating the “power” of ultraviolet radiation (UV rays) for K-12 students using our Color Changing UV Beads and a plastic prescription bottle.

Upon refilling a prescription at his local pharmacy, Jim noticed a marking on his brown prescription bottle that read – “UV BLOCKING PLASTIC.” Being the solar science enthusiast he is, Jim immediately filled an empty prescription bottle with Energy Beads. To his amazement, the bottle blocked out nearly 100% of the UV light! Come to find out, many drugs are sensitive to damaging UV light, so the bottle is specifically designed to preserve the life of your prescription.


Check out Color Changing UV Beads here!

Experiment Materials

  • One of those brownish prescription bottles
  • Color Changing UV Beads

Experiment Videos


Bucket of UV Beads


Find ultraviolet (UV) beads to use in the experiment. You can use an assortment of colors or a single color.

UV Bead - Prescription Bottle Test


Get an empty prescription bottle (ask an adult for help with this).


While indoors, and away from UV rays, add UV beads to the prescription bottle.


Take the bottle outside and leave it there for 3 minutes.


After 3 minutes have elapsed, take your prescription bottle back inside. Remove the beads from the container and note the color change that did or did not occur.

How Does It Work

UV Beads have a chemical substance embedded into the plastic that will change color when exposed to UV radiation (sunlight). The beads will remain white indoors, as long as they are kept away from windows or doors where UV light can “leak” into the room. Many prescription bottles have a chemical embedded into the brownish plastic that blocks out almost 100% of the UV light that might cause damage to the medicine. Using the UV Beads as a substitute for the medicine in the prescription bottle is a great way to test how effectively these bottles and others block the UV rays.

Science Fair Connection

Jim Stryder’s idea would be great to explore for a science fair project. However, you can’t just put UV Beads in a prescription bottle and call your project finished. If you just put the beads in the bottle to show that the bottle blocks the UV rays, you’ve merely demonstrated the concept — it is a science demonstration, not an experiment. To make the UV Beads and prescription bottle activity a science fair project, you have to change something (identify a variable), run some more tests, and make some comparisons.

  • Find several different types of medicine bottles and test to see which one is the most effective in blocking the damaging UV rays of the sun. For this experiment, be sure to use the same number and color of UV Beads and expose the beads to the sunlight through the bottle for the same amount of time to standardize the conditions as much as possible.
  • Examine the UV blocking powers of other types of bottles, such as plastic vs. glass bottles or different brands or styles of water bottles.
  • What else claims to have UV blocking powers? Sunglasses? Window tinting films? Camera lens filters? Sunscreen? Choose a variable and run some tests to see if the UV blocking claims are true. For example, are polarized sunglasses really that much better than regular sunglasses at blocking out the harmful UV rays of the sun?

There are many ways to use UV Beads for a science fair project. We have written up a sample science fair experiment called Revealing UV with Color-Changing Beads that walks you through a project step-by-step. If you are interested in a simple, straightforward, and quick science fair project, be sure to check it out.